U.S. patent number 4,874,010 [Application Number 07/199,216] was granted by the patent office on 1989-10-17 for heater control valve.
This patent grant is currently assigned to Siemens-Bendix Automotive Electronics Limited. Invention is credited to Allan W. DeJong, Paul D. Perry.
United States Patent |
4,874,010 |
DeJong , et al. |
October 17, 1989 |
Heater control valve
Abstract
A heater control valve comprising: a valve body defining a
chamber and a bypass passage extending therefrom. A first conduit
in fluid communication with the bypass passage for defining a first
inlet port and a first exit port adapted to communicate coolant to
an external device. A second conduit, in communication with the
chamber defining a second inlet adapted to receive flow from the
external device and a second outlet. The valve body further
including a first seating surface disposed about an upstream end of
the bypass passage and a second seating surface disposed about the
second inlet, and a bypass valve, rotatable from a first position
in sealing engagement with the first seating surface to a second
position in sealing engagement with the second seating surface, and
an actuator, for rotating the bypass valve from the first position
to the second position in response to control signals.
Inventors: |
DeJong; Allan W. (Chatham,
CA), Perry; Paul D. (Chatham, CA) |
Assignee: |
Siemens-Bendix Automotive
Electronics Limited (Chatham, CA)
|
Family
ID: |
22736670 |
Appl.
No.: |
07/199,216 |
Filed: |
May 26, 1988 |
Current U.S.
Class: |
137/484.4;
165/284; 137/625.29; 137/110 |
Current CPC
Class: |
B60H
1/00485 (20130101); F16K 11/052 (20130101); F16K
17/34 (20130101); Y10T 137/86726 (20150401); Y10T
137/7755 (20150401); Y10T 137/2562 (20150401) |
Current International
Class: |
B60H
1/00 (20060101); F16K 11/052 (20060101); F16K
17/20 (20060101); F16K 17/34 (20060101); F16K
11/02 (20060101); G05D 011/035 () |
Field of
Search: |
;137/599.1,117,484.4,625.29,522,523,110 ;165/38 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Hepperle; Stephen
Attorney, Agent or Firm: Wells; Russel C. Boller; George
L.
Claims
I claim:
1. A fluid control valve comprising:
a valve body defining a chamber and a bypass passage, for receiving
fluid, extending therefrom,
first conduit means, in fluid communication with the bypass
passage, for defining a first inlet adapted to receive fluid and a
first outlet adapted to communicate fluid to an external
device;
second conduit means, in communication with the chamber for
defining a second inlet, adapted to receive flow from the external
device, and a second outlet;
the valve body further including a first seating surface, within
the chamber, disposed about a downstream end of the bypass passage
and a second seating surface disposed about the second inlet within
the chamber;
flow control means for regulating the flow rate of fluid, from the
first inlet to the first outlet, to a maximum value, and for
prohibiting fluid flow through the external device by terminating
fluid communication between the second inlet and second outlet
wherein the flow control means comprises;
a bypass valve, rotatable between a first position in sealing
engagement with the first seating surface and a second position in
sealing engagement with the second seating surface.
2. The valve as defined in claim 1 including an actuator means
comprising an axially movable member offset from the axis of
rotation of the bypass valve and means connecting the axially
movable member to the bypass valve for converting the axial motion
of the member to rotary motion to rotate the bypass valve.
3. The valve as defined in claim 1 wherein the flow control means
comprises
actuator means operatively connected to the bypass valve for
rotating same to the second position in response to a control
signal;
means for generating a bias force upon the bypass valve to maintain
same in sealing engagement with the first seating surface below
fluid flow rates less than a predetermined level and for permitting
the bypass valve to rotate against the bias force, under the action
of the fluid force generated by diverted fluid to regulate fluid
flow at the first outlet at the predetermined level.
4. The valve as defined in claim 3 wherein the actuator means
comprising an axially movable member offset from the axis of
rotation of the bypass valve and means connecting the axially
movable member to the bypass valve for converting the axial motion
of the member to rotary motion to rotate the bypass valve.
5. The valve as defined in claim 4 wherein the actuator means
includes the bias means, and wherein the bias means is coupled to
the axially movable member to urge same in a direction to urge the
bypass valve toward the first seating surface.
6. A fluid control valve comprising:
a valve body defining a chamber and a bypass passage, for receiving
fluid, extending therefrom,
first conduit means, in fluid communication with the bypass
passage, for defining a first inlet adapted to receive fluid and a
first outlet adapted to communicate fluid to an external
device;
second conduit means, in communication with the chamber for
defining a second inlet, adapted to receive flow from the external
device, and a second outlet;
the valve body further including a first seating surface, within
the chamber, disposed about a downstream end of the bypass passage
and a second seating surface disposed about the second inlet within
the chamber;
a bypass valve, rotatable between a first position in sealing
engagement with the first seating surface and a second position in
sealing engagement with the second seating surface;
actuator means, operatively connected to the bypass valve for
rotating same from the first position to the second position in
response to control signals, and for generating a bias force upon
the bypass valve to maintain same in sealing engagement with the
first seating surface below fluid flow rates less than a
predetermined level and for permitting the bypass valve to rotate
against the bias force, under the action of the fluid force
generated by diverted fluid to regulate fluid flow at the first
outlet at the predetermined level.
7. The valve as defined in claim 6 wherein the first conduit means
includes flow diverter means for urging fluid to flow into the
bypass passage.
8. The valve as defined in claim 7 wherein the diverter means
includes an arcuate shaped deflector extending from a wall of the
first conduit means.
9. The valve as defined in claim 8 wherein the deflector terminates
below and spaced from the opening of the bypass passage.
10. The valve as defined in claim 8 wherein the deflector is
positioned upstream of the center of the bypass passage.
11. The valve as defined in claim 8 wherein the centerline of the
first inlet is lower than the centerline of the first outlet.
12. The valve as defined in claim 6 wherein the bypass valve
comprises hinge means, including a hinge pin, rotatable by the
actuator means and first and second spaced resilient seals
rotatable therewith for respectively engaging the first and second
seating surfaces.
13. The valve as defined in claim 12 wherein the bypass valve
further comprises:
a first member terminating at one end in an eyelet adapted to
receive and rotate with the hinge pin, and wherein the first and
second resilient seals are annular and secured about the first
member.
14. The valve as defined in claim 13 wherein the actuator means is
drivingly connected to one end of the hinge means and includes a
spring for biasing the bypass valve toward the first seating
surface and means for moving the bypass valve, against the force of
the spring, into engagement with the second seating surface.
15. The valve as defined in claim 14 wherein the actuator means
comprises an axially movable stem offset from the axis of rotation
of the bypass valve and including connecting means, connecting an
end of the stem to the hinge means, for converting the axial motion
of the stem to rotary motion of the hinge means.
16. The valve as defined in claim 15 wherein one end of the hinge
pin extends from the valve body, the connecting means comprises a
bell lever interconnecting the stem and the hinge pin.
17. The valve as defined in claim 16 wherein the bell lever and
hinge pin are of integral construction, the bell lever including an
extending pivot member and wherein the one end of the stem includes
an opening and resilient member for receiving the stem end and for
securing the pivot member thereto.
18. The valve as defined in claim 15 wherein the actuator means
includes a vacuum motor comprising a vacuum chamber including at
one end thereof a flexible diaphragm, movable in a first direction,
in response to a vacuum signal, and wherein the spring is located
within the vacuum chamber, for urging the diaphragm in an opposite
second direction, and wherein the stem is operatively secured to a
stem and movable with the diaphragm.
19. The valve as defined in claim 12 wherein the hinge pin is
received within a stepped bore, extending through the valve body to
the chamber and an oppositely situated blind bore and wherein the
hinge means includes a seal for fluidly sealing the hinge pin and
stepped bore.
20. The valve as defined in claim 6 wherein the first inlet is
substantially coaxial with the bypass passage.
Description
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates generally to flow control valves and
more particularly to a flow control valve which regulates coolant
flow to a heater core.
Heater cores such as those used in automotive vehicles receive hot
coolant from the engine. The rate of coolant flow is proportional
to engine speed (rpm). It is known that over the life of a vehicle
the coolant may be contaminated with particles of grit, rust, etc.
which also flow through the core. In order to increase the useful
life of the heater core and protect it, it is necessary to limit
the flow rate of the coolant through the heater core to reduce
erosion due to the impact of the particles with portions of the
core. Further, during the useful life of the heater core sediment
within the coolant may accumulate on the various internal passages
of the heater core which tends to restrict the flow of coolant
therethrough. Consequently, as the heater core ages the pressure
drop across the core increases. It is also useful to limit the
maximum flow rate of coolant through the heater core to maintain
the pressure within the core at reasonable levels otherwise the
core may flex, leak or fatigue prematurely. It has been found that
if the flow rate of coolant is restricted to approximately 5-6
gallons/minute ( 19-23 liters per minute) heater core useful life
can be increased. The above relationship has been appreciated for
some time. Current heating systems utilize a rubber orifice flow
control washer. This device provides a restriction at all flow
rates. As the flow pressure increases the rubber compresses causing
the flow area (orifice diameter) to decrease thus limiting the flow
to the required amount. While the rubber orifice functions to limit
the maximum flow rate of coolant, it also provides a significant
restriction to the flow of coolant at lower engine rpm thus
restricting the amount of coolant communicated to the heater and
reducing its performance.
It is an object of the present invention to provide a flow control
valve for a heater core which maximizes flow at low engine rpm and
which limits coolant flow to approximately 6 gallons per minute at
high engine rpm. Another object of the present invention is to
controllably terminate coolant flow to the heater core under
certain conditions such as when maximum air conditioning
performance is required.
Accordingly, the invention comprises: a heater control valve
comprising: a valve body defining a chamber and a bypass passage
extending therefrom, first conduit means in fluid communication
with the bypass passage for defining a first inlet port adapted to
receive coolant and a first exit port adapted to communicate
coolant to an external device such as a heater core, including flow
diverter means to urge coolant to flow into the diverter passage.
The control valve further comprising second conduit means, in
communication with the chamber for defining a second inlet adapted
to receive flow from the external device and a second outlet. The
valve body further including a first seating surface disposed about
an upstream end of the bypass passage and a second seating surface
disposed about the second inlet. A bypass valve, is located in the
valve body, rotatable from a first position in sealing engagement
with the first seating surface to a second position in sealing
engagement with the second seating surface and, includes a hinge
pin extending from the valve body; and actuator means for rotating
the hinge pin and bypass valve from the first position to the
second position in response to control signals and for generating a
bias force upon the bypass valve to maintain same in sealing
engagement with the first seating surface below coolant flow rates
less than a predetermined level wherein the bypass valve is
permitted to rotate against the bias force, under the action of the
fluid force generated by the diverted coolant to regulate coolant
flow at the first outlet at the predetermined level.
Many other objects and purposes of the invention will be clear from
the following detailed description of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In The Drawings:
FIG. 1 is a cross-sectional view of one embodiment of a flow
control valve constructed in accordance with the present invention
and is taken along line 1-1 in FIG. 4.
FIG. 1a illustrates a portion of the flow control valve.
FIG. 1b issue a bottom view of a cap.
FIG. 2 illustrates a front elevational view of the flow valve.
FIG. 3 illustrates a top elevational view of the flow valve.
FIG. 4 illustrates a right side elevational view of the flow
valve.
FIG. 5 illustrates an alternate embodiment of the present
invention.
FIGS. 6 through 9 illustrate various views of a bypass valve used
in the above flow valves.
FIG. 10 illustrates a flow rate to the heater core vs rpm
curve.
FIG. 11 and 11a illustrate an alternate embodiment of the
invention.
FIG. 12 illustrates still another embodiment of the invention.
DETAILED DESCRIPTION OF THE DRAWINGS
With regard to FIGS. 1-4 there is illustrated a flow valve
generally shown as 20. The flow valve 20 comprises a valve body 22
and an actuator assembly 24. Only a portion of the actuator
assembly 24 is shown in FIG. 1 since it extends forward of the
valve body (see FIG. 4). The valve body includes a plurality of
tubes or conduits connected in an "H" configuration. Lower tubes
30a and 30b are connected to the upper tubes 30c and 30d via a
bypass body section generally illustrated as 40. The bypass body
section 40 includes a central cavity 42 in direct communication
with the tubes 30c and 30d. The valve 20 further includes a cap 50
which comprises a generally rectangular first portion 52 which may
be snap-fit about a shoulder 54 formed about the upper portion of
the bypass body section to enclose the cavity 42. Appropriate
sealing such as a rubber gasket or O-ring 56 may be used to enhance
the seal. The O-ring 56 may be pressed by a bead 55. The cap 50
further includes a second portion 56 which extends from the first
portion to cantilever mount the actuator assembly. The second
portion includes a central opening 220, to receive a stem 110 of
the actuator assembly, and a plurality of arcuate openings 222
positioned thereabout.
The bypass section further includes a bypass passage 44 in
communication with tubes 30a and 30b. The lower portion of the
chamber 42 proximate the bypass passage 44 defines a seating
surface 46. Similarly the portion of the bypass body section
proximate the innermost portion of tube 30c defines a second
seating surface 48. The tubes 30a and b essentially form a single
conduit forming at one end a first inlet 32a and at another end a
first outlet 34a. Tubes 30c and 30d define another conduit having a
second inlet 32b and outlet 34b. The inner diameter of tube 30c may
be tapered from the second inlet 32b to the second seating surface
48.
Rotatably secured within the bypass body section 40 is a bypass
valve generally shown as 60. The bypass valve 60 includes a door
hinge 62 (shown in greater detail in FIGS. 6 and 7) and the two
rotate as a unit. As can be seen more clearly in FIGS. 6 and 7, the
door hinge includes a cylindrical eyelet portion 70 defining an
opening 72 for receipt of a hinge pin 74 (shown more clearly in
FIGS. 1 and 4). Extending from the eyelet portion 70 is a
relatively flat member 76 comprising a plurality of openings 78 the
purpose of which will be described below. The flat member 76
comprises a generally rectangular portion 80 extending from the
eyelet 70 and a generally semicircular portion 82. The diameter of
the semicircular portion may be slightly less than the width of the
rectangular portion 80. The semicircular portion 82 further
includes at least one protuberance 84.
The bypass body section, as shown in FIG. 1a, includes a first
cylindrical projection 200 defining a stepped bore 202 and opening
204. Positioned oppositely is a second cylindrical projection 206
defining a blind bore 208. During fabrication of the valve 20 the
bypass valve 60 is inserted into the chamber 42 and aligned to the
opening 204. The hinge pin 74 with an O-ring 210 is inserted into
the stepped bore 208. The hinge pin 74 may include a serrated edge
or similar connection means, which engages the eyelet 70.
The bypass valve 60 further includes a resilient sealing member 90
shown in FIGS. 1, 8 and 9. The sealing member 90 includes
oppositely extending annular sealing surfaces 92a and 92b. The
sealing member 90 may be injection moulded to the door hinge 62
such that the resilient material fills the openings 78 thereby
securing the resilient material thereto. As mentioned above, the
sealing member 90 has a generally circular profile and it is
desirable that the outer edge 94 of the member 90 be formed
essentially tangential to the protuberance 84 of the door hinge
80.
The door hinge 62 is rotatable with the hinge pin 74 which extends
through the bypass body section 40. Attached to one end of the
hinge pin 74 is a bell crank lever 100. The bell crank lever may
include an opening 102 of prescribed shape to receive a similarly
formed end of the hinge pin 74. The bell crank lever 100 further
includes another opening 101 to receive a portion of an actuator
stem 110.
As mentioned above, the valve 20 includes an actuator assembly 24.
As illustrated in the accompanying figures, the actuator assembly
comprises a vacuum motor 120 comprising a multipart housing 122
(housing portions 124a and b) which secure therebetween a rolling
diaphragm 126. The lower housing portion 124b is adapted to be
supported by the cap 50. More particularly the lower housing
portion 124b includes a flange and opening 232 received into the
opening 220 of the cap 50. In addition the lower housing portion
124b includes a plurality of barbs 234 adapted to fit into the
openings 222 thereby securing the actuator assembly 24 to the cap
50. While a vacuum motor 120 is shown it should be appreciated that
electric actuators such as stepper motors or solenoids can be used
to actuate the stem 110.
Attached to the upper side of the diaphragm is a cup-shaped piston
128 comprising a threaded bore 130 adapted to receive one end 132
of the stem 110.
The vacuum motor 120 further includes a vacuum inlet port 134
adapted to communicate vacuum to a chamber 136 partially defined by
the diaphragm 126. A spring 138 biases the diaphragm 126 and stem
110 downwardly in a manner to urge the bypass valve 60 to seat upon
the seating surface 46 as illustrated in FIG. 1.
With reference to FIG. 1, the valve 20 may further include an
optional flow director 140 positioned within the flow passage
defined by tubes 30a and 30b and located such that coolant received
at the inlet 32a will be diverted upwardly into the bypass passage
44. As illustrated in FIG. 1 the diverter comprises an arculately
shaped portion of tubing, situated slightly left of center of the
bypass passage 44, which extends perpendicular to the plane of the
cross-section.
In operation coolant is pumped from the engine at a rate
proportional to engine speed (see FIG. 10), and is received at the
inlet 32a. Some of the coolant impacts the diverter and a portion
of the flow is diverted upwardly into passage 44 and thereafter out
of the exit end 34a of tube 30b into the heater core 38. The flow
from the heater core returns to the valve 20 through the inlet 32b
of tube 30c and exits the valve 20, at 34b, and is communicated to
a radiator. Communication to the engine core and radiator may be
affected by utilizing rubber hoses 150 such as those shown in FIGS.
2 and 3. Without vacuum applied to the port 134, the spring 138
biases the stem 110 downwardly in a manner to urge the valve 60 to
close the bypass passage 44. As engine speed increases the rate of
fluid flow will increase through tube 30a as will the upward force
of that portion of the coolant diverted into the bypass passage 44.
The spring 138 in the vacuum valve 120 and the effective length of
the bell crank lever have been set to maintain the valve 60 in its
closed position for flow rates below approximately 5 gallons per
minute. As the engine speed increases the pressure exerted on the
lower face 96 of the valve 60 will cause it to rotate clockwise, as
seen in FIG. 1, against the bias force of the spring 30 thereby
opening the bypass passage 44 regulating the coolant flow rate
communicated to the core at approximately 5 to 6 gallons per
minute. For many vehicles at maximum rpm, the engine will generate
a coolant flow in the vacinity of 15 to 16 gallons per minute (see
dotted line, FIG. 10). In operation the valve 20 will limit the
flow to the core at less than 6 gallons per minute while bypassing,
through the bypass passage 44, up to 10 gallons per minute.
At low engine rpm, that is, at engine rpm below the level that
would cause the valve 60 to open, it is desirable that the valve 20
does not restrict the flow of fluid to the core 38. This is
accomplished by sizing the flow area 150 between the top of the
diverter 152 and sides 154 of tube 30a.
During engine operating conditions such as maximum air conditioning
performance when it is desired to completely terminate flow through
the heater core engine vacuum is supplied to the vacuum port 134
through a control unit such as to an electric vacuum controller 160
of known variety. The vacuum so communicated to the vacuum motor
120 causes the diaphragm 126 and stem 110 to move upwardly thereby
rotating the lever 100 and valve 60 to seat against the sealing
surface 48 thereby prohibiting flow through the core 38. In this
mode of operation all of the engine coolant is diverted to the
radiator through the bypass passage 44.
As mentioned above, the diverter 140 is optional and can be
eliminated from tubes 30a and b. In this configuration the fluid
pressure in tubes 30a and b will increase in proportion to flow due
to the flow restriction of heater core. At a given flow rate fluid
will be diverted into the bypass passage 44, to cause the diverter
valve 60 to begin to open.
FIG. 5 illustrates an alternate flow valve 20'. The valve 20' of
FIG. 5 is identical to that described in FIG. 1 with the exception
of the configuration of tubes 30'a and 30'b. More particularly, the
center line of tube 30'a is located below the center line of tube
30'b such that the interior end 200 of tube 30'a may be formed with
a continuous transition i.e. diverter 202' terminating the inlet of
tube 30'b. The diverter 202' may comprise a quarter circle of
tubing which terminates at a downstream point 204' slightly to the
right of the downstream wall 206' of the bypass passage 44. This
diverts the water flow to impact the door to cause it to open. This
effect increases as flow increase to cause more bypass at high rpm
and less restriction at low rpm.
FIGS. 11 and 11a illustrate an alternate embodiment of the present
invention. More particularly, the cup-shaped piston 128, having the
threaded bore 130 to receive the stem 110, has been replaced by a
single piece piston assembly 250. The piston assembly 250,
preferably fabricated of plastic includes piston 128' and
integrally attached stem 110'. The stem 110' includes a flat
section 252 including axially extending ribs 254a,b to provide
strength. The lower portion of the stem is bi-furcated at 256a,b to
define a flexible plastic member 260 and opening 262. FIG. 11a
illustrates an alternate hinge pin and bell crank configuration
shown as 270. In this configuration, the bell crank lever 110' and
hinge pin are integrally formed. The crank lever 100' includes an
outwardly extending pivot member or pin 272 which includes a barbed
end 274. The barbed end 274 is adapted to be received within the
opening 262 of the stem 110' and secured thereto by the flexible
member 260.
FIG. 12 shows a partial cross-sectional view of the lower portion
of the valve 20. As can be seen diverters such as 140 and 200 have
been eliminated and the inlet 30a' substantially coaxially to the
bypass passage 44. In operation coolant received at the inlet
directly impacts the bypass valve 60 urging same off from its
seat.
Many changes and modifications in the above described embodiment of
the invention can, of course, be carried out without departing from
the scope thereof. Accordingly, the scope is intended to be limited
only by the scope of the appended claims.
* * * * *